1. Field of the Invention
The subject invention relates to novel water-dispersible copolymers which contain a UVA light-absorbing monomer, a UVB light-absorbing monomer, and a hydrophilic monomer component. The copolymers may optionally contain a hydrophobic monomer component. Because of their broad range of UV absorbency, the copolyesters may be used in fabric care compositions, personal product compositions, and in other applications recognized by those skilled in the art.
2. Prior Art
The harmful effects of solar radiation are well known. The UVB (290-320 nm) portion of the solar spectrum is largely responsible for erythema (sunburn) and cancer (M. M. Rieger, Cosmet. Toiletries, 102(3):91 (1987); C. Taylor, Skin Cancer Foundation J., 4:90 (1986)). The UVA (320-400 nm) portion of the solar spectrum is believed to be responsible for skin aging and premature wrinkling (L. H. Kligman, F. J. Akin, and A. M. Kligman, J. Invest. Dermatol., 84:272 (1985)).
In addition, UV light is also known to fade garments, especially in areas of high solar intensity. This problem has been partially addressed via the application of various monomeric chromophores to garment surfaces (U.S. Pat. No. 4,153,744 to K. H. Remley; U.S. Pat. No. 4,788,054 to R. J. Bernhardt et. al; P. C. Crews, et. al., Text. Chem. Color, 11:21 (1987); B. Milligan et. al., Polym. Degrad. Stab., 10(4):335 (1985)).
None of the above references relating to the protection of garments from solar radiation teach the use of polymeric UV light-absorbers.
Several examples of polymeric UV light-absorbers have been prepared which selectively filter out either UVB or UVA light at maximum absorbance (.lambda.max), but not both portions of the solar spectrum at maximum absorbance. In addition, none of the following references teach the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer.
U.S. Pat. 3,864,473 to Ciaudelli teaches the use of 4-dimethylaminobenzoate-grafted poly(ethyleneimine) as a polymeric UV light absorber. The use of the aminobenzoate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. Moreover, the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
U.S. Pat. No. 4,524,061to Cho et al. teaches the use of poly(methacrylate)/poly(vinylpyrrolidone)/poly(vinyl 4-aminobenzoate) copolymer as a polymeric UV light absorber. The use of the aminobenzoate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. Moreover, the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
French Patent 2,617,399 to Lapoiriere et al. teaches the use of cinnamate-grafted poly(acrylamide) as a polymeric UV light absorber. The use of the cinnamate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. Again, the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
U.S. Pat. No. 4,545,980 to Hill teaches the use cinnamate-grafted poly(dimethylsiloxanol) as a polymeric UV light absorber. The use of the cinnamate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. Once more, the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
Japanese Patent 60,099,186 to Pola Chemical Industries, Ltd. teaches the use of poly(glycidol)/poly(4-glycidylaminobenzoate) copolymer as a polymeric UV light absorber. The use of the aminobenzoate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. As with the other above-cited art, the use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
B. Jacquet et al., Rev. Gen. Caoutch. Plast., 54(575):85 (1977) teach the use of poly(vinyl stearate)/poly(vinyl (4'-dimethylaminobenzoyloxy)acetate) copolymer as a polymeric UV light absorber. The use of the aminobenzoate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. Neither the use of a hydrophobic nor a hydrophilic component to control the dispersibility and adsorption properties of the polymer is taught.
German Patent 2,726,568 to Jacquet et al., teaches the use of cyanodiphenylacrylic acid-grafted poly(vinyl acetate) as a polymeric UV light absorber. The use of the cyanodiphenylacrylate chromophore alone, however, limits the polymer's maximum absorbance to the UVB range. As above, neither the use of a hydrophobic nor a hydrophilic component to control the dispersibility and adsorption properties of the polymer is taught.
U.S. Pat. No. 4,839,160 to Forestier et al. teaches the use of benzylidenecamphor-grafted poly(acrylamide) as a polymeric sunscreen. The use of the benzylidenecamphor chromophore alone, however, limits the polymer's maximum absorbance to the UVA range. The use of either a hydrophobic or hydrophilic component to control the dispersibility and adsorption properties of the polymer is not taught.
In each of the above-identified references, the polymers used differ from the copolymers of the subject invention both in that there is no teaching of the use of both a UVA and a UVB light-absorbing monomer to selectively filter out both UVB and UVA light at .lambda.max; and that there is no teaching or suggestion that the UVA and UVB light-absorbing polymer can be hydrophilicly or hydrophobicly modified to control the dispersibility and adsorption properties by the addition of a hydrophilic or hydrophobic monomer.
In U.S. Ser. No. 731,565, filed Jul. 17, 1991, the parent of the subject application, there is taught a water-soluble or water dispersible copolymer containing a UV-absorbing monomer. It is not clear from this reference, however, that there must be present both a UVA-absorbing and a UVB-absorbing monomer to provide the broad spectrum absorbing alcohols obtained using the polymer of the invention.
Thus, there is a need in the art for novel copolymers comprising both a UVB light-absorbing monomer and a UVA light-absorbing monomer, as well as a hydrophilic monomer which allows the polymer to be solvated in aqueous media, and optionally a hydrophobic monomer to fine-tune the polymer's ability to adhere to a desired surface.